Monthly Archives: April 2026

Klystronics at the 1994 Atlanta CoCoFest – revealed

At the 1994 Atlanta CoCoFest, the following vendors were present:

Booth 20 was unoccupied, as the vendor did not make it. They did leave a stack of flyers explaining their absence. You can read the text of that flyer in the previous post.

Who was Klystronics? Beyond those that knew about it in 1994, the backstory was explained in my CoCoFest Chronicles book which you can download for free at the Color Computer archive.

First, my fest report text file (included in the book) alluded to it in the opening:

NOTE: Any discrepancies between what is contained in this report and what is real is merely coincidental. This includes, but is not limited to, names, locations, events, and inside jokes (like klystrons).

– Allen Huffman’s 1994 Atlanta CoCoFest report text file

That report also mentioned the booth:

Klystronics — Another new vendor. This group was offering a large supply of “gently used” klystrons, complete with manuals. The minimal water damage their inventory had didn’t seem to effect operation, though the yellow discoloration made them no longer match the CoCo’s case.

– Allen Huffman’s 1994 Atlanta CoCoFest report text file

…but the full backstory was not explained until the book itself came out a few years later. From the book:


MORE BEHIND THE SCENES

The Story About Klystronics

One of the more interesting tales I get to tale is that of the “mysterious” vendor, Klystronics. They were listed in the Fest booklet, and even had a table which was empty except for some flyers and an empty business card holder. To the casual observer (i.e. someone who fell for it) it would appear they just didn’t make it to the show. To the less casual observer, one might have found some of the information on the flyer a bit curious.

Klystronics was a practical joke played for the benefit of one individual, Nick Johnson. At the time, Nick was hanging out on the GEnie online service (thanks to its then-outstanding Star*Services which offered unlimited non-prime access for about five dollars per month). Nick had a macro he would use far too often while in chat sessions which said “PLEASE DO NOT URINATE ON THE KLYSTRON.” Terry Todd and myself found this quite annoying.

At some point, our friend Bob Rutherford got together with us and we came up with the idea of Klystronics. Once the name was created, the joke fell into place. We acquired a booth, printed flyers (using a font I had never used for any Sub-Etha literature), and purchased a business card holder.

At the show, Nick wandered over and said “hey, did you guys know there is a company here called Klystronics?” or something to that effect. We held in laughter. He most likely was suspicious but if so he played along pretty well. The flyer had some meaningless babble about CoCo compatible Klystrons, but embedded in the words were numbers enclosed in brackets. If you put the letter next to the numbers together in numerical order you would decode the hidden message which basically clued one in to the fact that this was just a joke. At first Nick suspected something far more clever for the origin of the numbers, but towards the end of the show I do believe he figured it out. I am not quite sure if we ever told him officially that it really was us.

A few others were in on this joke, most notable Colin McKay. After the Fest, Colin played up the existence of Klystronics on the internet CoCo mailing list after someone wondered just who they were. Even Mike Knudsen chimed in observing that certainly they had nothing to do with the “klystron” tubes he was familiar with! He certainly was right. I have in my possession (thanks to Mike’s archives) a copy of the Klystronics message thread and I must say — it really makes me proud seeing how well this went over.

The following Fest, we planned to do more including having Bob Rutherford build a rather amazing device to attach to a CoCo. We never quire followed through, but Klystronics lived on in my Fest report — even though there was no booth nor mention of them in the official Fest booklet.

And now you know … the rest of the story. Maybe the comment about “water damage” will make a bit more sense.

Or, more likely, it will not.


I decided to post the original Kystronics flyer text on April 1, 2026. This was more involved than I expected. First, the raw text file seemed to use some embedded formatting codes. I could not remember what created them:

.pl1
.lm0
.ll137
.nf

This led me to trying to figure out how to export the document in a formatted version to match what I did back in 1994. I was using the text editor VED under OS-9 at the time, and suspected maybe I was using the companion VPT text formatted. After figuring out how to run it off my old OS-9 hard drive image in an emulator, I learned it did not like these codes.

Eventually, I just decided to feed it into A.I. (Copilot) and let it do it for me. It presented me with an ASCII version of document, correctly figuring out what codes mean blank lines, and what codes meant centered lines. BUT, it was 137 columns wide.

What? That wouldn’t even fit if I printed in landscape mode, which wasn’t even a thing on that printer back then.

A bit more research revealed I likely printed this on my Tandy DMP-132 printer in condensed mode, which would indeed allow 137 characters per line with a bit of margin on each side.

This led me to just simulating it by using a condensed dot matrix font and turning the text into a PDF.

That’s close-ish.

Some things seem obvious now…

As I pointed out, I tried to use a font Sub-Etha Software didn’t use for printing flyers, and change things up so it was not immediately obvious I created this. For instance, it spells “disc” with a C and I never did that. It also uses “Coco” without the second C capitalized. But, as I look at it now, I see a few things that would have tipped folks off.

  • First, back then, I typed DOS as “Dos” as if it was a word. So did Klystronics. (And other folks of that era, but still, a hint.)
  • Also, “S.E.S.” Dos and “B.H.” Dos? I’ve never heard of any RS-DOS replacements with those initials, but there were two companies at the fest that had matching initials.
  • I also misspelled separately the same way I’d be misspelling it today if it wasn’t for auto-correct. And so did Klystronics. My Fest reports were full of that misspelling as well as mixing of where/were.
  • Bored member? “lol”. That misspelling was intentional.

The document also has some things that could further tip off the joke.

  • 16K RAM, but also supporting the Hi-Res Joystick Interface? Seems unlikely.
  • Color Computer 2 but NOT Color Computer 1? Why would that be?
  • Also, the name “Graham Cain” alluded to the two individuals behind it. One may be obvious, the other not at all.

But … the biggest tip was that there is also an encoded message hidden in this document. Look at the full text and see if you can decode it. That was the actual reveal.

Until next time…

Klystronics at the 1994 Atlanta CoCoFest

Fine Klystrones Since 1989

HELLO! We are[14] sorry that we were unable to personally attend this[1] year’s CocoFest. We had some commercial accounts we needed to attend to and thus were unavailable. We hope to see you[9] next year at the 1995 Chicago CocoFest or at the upcoming Klystrone Con[4] ’95 in Aneheim.

WHAT IS KLYSTRONICS?

Klystronics, Inc. is an independent organization dealing in the sale and service of both new and used Klystrones.

WHAT IS A KLYSTRONE?

Klystronics, Inc. is an independent organization dealing in the sale and service of both new and used Klystrones.

WHY IS KLYSTRONICS AT A COCOFEST?

One of our[11] bored members, Graham Cain, got his start in the electronics field with a[3] TRS-80 Color Computer which was part of an in-home study course. His projects led him into P.C. interfacing and, along with other business partners, the formation of Klystronics in 1989. Most of the projects were industrial in nature and involved the usage of Klystrone units with commercial grade P.C. components, but Graham, remembering his roots with the Coco, used his knowledge and spare time to create a Coco Klystrone interface. Thus, Klystronics offers it’s services to both industrial users and Color Computer users.

HOW CAN I ORDER A KLYSTRONE FROM KLYSTRONICS?

Since we are[6] unable to take orders personally, you[13] can mail in your order or use our toll free 1-800 telephone ordering service. We accept personal and business checks, credit cards (Visa, MasterCard, Diner’s Club, Discover[10]), money orders, international postage, and C.O.D.s.

KLYSTRONE SYSTEM REQUIREMENTS:

o Color Computer 2 or 3
o Y-Cable of Multi-Pak Interface
o Cassette Cable (if[8] sound desired)
o Floppy Disc Drive (S.E.S./B.H.[5] Dos)

o 16K of R.A.M. or greater
o Hi-Res Joystick Interface
o Color Monitor recommended
o OS-9 Drivers Sold Seperately

TECHNICAL SUPPORT FOR KLYSTRONE QUESTIONS:

Support is[2] provided 24 hours a day via long distance phone calls, or use our free computer bulletin board service (300-1200 baud). We may also be contacted via Prodigy, though response time may be slow. We are not responsible[7] if the message[12] is lost.

CONTACT

Please use the latest address and phone information as listed on our business cards.

FEST SPECIAL[15]!!!!! USED KLYSTRONES (SLIGHT WATER DAMAGE) 37% OFF!!!!!